Over the years, many problems have been encountered in attempting to automate the mechanical assembly of electric devices, particularly electric tools provided with electric motors. Although some of the difficulties in such mechanical assembly have been overcome, for example in the production of electric motors and the insertion of these motors in housing shells of portable power tools, a problem that has remained is the completion of the wiring of these tools. The use of printed circuit boards has reduced this wiring problem in some instances, so also has the proposal to employ a plug connection from a printed circuit board to the windings of the electric motor as disclosed in Swiss Pat. No. 568,679.
However, some manual operations in completing the wiring are still essential. For example, the use of a plug connection, although simplifying assembly, still requires the plugging to be performed by hand, as also necessary soldering connections have to be made by hand.
Moreover, the use of printed circuit boards does have the disadvantage, particularly when comparatively large electric currents are involved, that wide conductor paths are necessary. These wide conductor paths not only increase the cost of manufacture of the printed circuit boards, but also result in space and insulation problems.
Another problem that arises in assembly of portable electric tools, is the positioning of the conductor wires in the tool's housing. Such conductor wires, particularly the motor supply wires, are multi-stranded so as to be readily pliable to enable an assembly operator to readily bend and position the wires in the tool's housing during and after insertion therein. Usually the cross-sectional area of these multi-stranded wires is less than 1 square millimeter.